除了斯图加特的Contessa工厂，按照雅尔塔的瓜分范围，除了德累斯顿以外，还有一个地方也在毛子的控制范围内.那就是图灵根州的耶拿，德累斯顿有蔡司的重要生产车间，耶拿才是蔡司的研发基地，这里还有肖特玻璃厂，耶拿被米军占领后不少德佬一流的光学专家被抢走到后来的西德，蔡司公司因为东西方分制也被一分为二.后来东德的蔡司产品都标上一个Jena已显示自己才是最正宗的.

美军对耶拿的轰炸：
The first U.S. bombing raid at Jena occurred on Friday 9 February 1945, when the United States Eighth Air Force (Mission 824) dispatched 1,296 bombers and 871 fighters in six separate forces. These were primarily targeting oil facilities in Germany, while also winning a war of attrition against the Luftwaffe who suffered a total 87 aircraft destroyed or damaged against 8 United States bombers and 5 fighters lost.
Nearly two thirds of the 311 U.S. bombers are reassigned to hit secondary targets, targets of opportunity for these 198 aircraft were the munitions industry in Weimar. Of these 198 B-17G “Flying Fortresses” aircraft, 11 bombed Jena shortly after noon damaging the city center and the northern quarter, including the Stadtkirche Sankt Michael (Church of St. Michael) and the Universitätshauptgebäude (University Library), with about 27 tons of bombs. In Jena this caused 98 deaths, 53 seriously injured, and another 204 slightly injured, while some 34 remained unaccounted for.
The second U.S. bomb raid at Jena occurred on Friday 23 February 1945, when the United States Eighth Air Force (Mission 843) dispatched 1,274 bombers in three groups, and 705 fighters. These were primarily targeting marshalling yards in Germany, while again combatting the Luftwaffe who suffered a total 31 aircraft destroyed or damaged against 1 United States B-24 “Liberator” bomber and 6 P-51 fighter aircraft lost. Of the 1,274 bombers, 368 were assigned to hit marshalling yards in Weimar, with 25 of the B-24’s targeting the yards in Jena. Nearly 60 tons of bombs started falling at 11:41 AM and striking in the North East of the city up to Löbstedt.
On Saturday, 17 March 1945 the United States Eighth Air Force Mission 892) again visited Jena. Mission 892 dispatched 1,328 bombers and 820 P-51 fighter aircraft in three groups to strike oil, industrial, and rail transportation targets in Germany. Owing to cloud coverage over some primary targets several B-17G aircraft of the second group were diverted to bomb secondary targets, these included the 71 B-17G that targeted the Zeiss works arriving over Jena at 1 pm. The city defenses and Luftwaffe had been weakened so that the B-17s dropped 210.7 tons of General Purpose (GP) explosive and fragmentation bombs, and 9 tons of incendiary bombs. Of these some dozen or fewer bombs struck the Zeiss and the Schott factories, the remainder striking the railway yard and other facilities.
Of this group of 449 B-17G, 1 was lost and 2 damaged beyond repair while 15 were damaged but repairable. The U.S.A.F. bombers lost 9 airmen Killed In Action (KIA), 1 P-51 pilot is KIA.
On Monday, 19 March 1945 the United States Eighth Air Force (Mission 896) again visited Jena in the strike that caused the most loss of life, severely damaging the historic downtown, again including the Church of St. Michael.
The Eighth Air Force records indicate this operation was originally planned to destroy airfields and industrial targets in Germany. The Eighth Air Force forces consisted of 1,273 bombers in three groups using visual and H2X radar, escorted by and 675 fighter aircraft. The Luftwaffe, though already severely depleted of fuel and experienced pilots, responded to this raid with more than one hundred fighters including a formation of 36 of the recently deployed Me 262 jet aircraft.
Cloud cover prevented 496 aircraft from accurately striking primary targets, so commanders of these groups directed the aircraft to bomb secondary planned objectives and these included the optical works at Jena which was bombed by 197 B-17G aircraft of the 3rd Air Division commencing at about 1:15 PM and concluding at 1:32 PM after some 563 tons of bombs were dropped. The bomb load included 800 incendiary devices that were dropped over the city center. The Zeiss factory was struck by about a half dozen bombs that had some effect. This one raid killed at least 134 people (in 2015 revised after studies by the City Historian to 236), leaving some 123 injured, and an estimated 12,000 people homeless. Almost every old building in the city center was damaged. Overall there were 1347 buildings damaged, of these 224 were total losses, while 261 suffered severe damage, 199 with moderate damage, and 663 with lighter damage; Jena had become the most devastated city in the State of Thuringia.
This bombing raid was witnessed by Lucas Van Hilst, he recounted in a letter sent to us at Company Seven:
“I was standing outside a zig-zag 'Schutzgraben' (protective ditch) looking up to 'my friends', the first wave of whom just passed by so to speak. Then suddenly a German soldier on leave grabbed me by the arm. “Mach’ schnell, 'runter!!”. The suction of an explosion threw me down the stairs. He may well have saved my life. In the center section several persons were killed or wounded. The last bombardment was the worst. The sight of carts loaded with dead bodies was shocking - as it would anywhere. That air attack did substantial damage to some Zeiss and also to Schott buildings (where one of my Dutch friends was killed). The rather small “Alte Stadt” (Old Town) was totaled. Visiting in 1994 it still was a sad sight.“
The losses of aircraft and crew in this region were reported as:
Luftwaffe: 3 aircraft were destroyed, 1 likely damaged beyond repair, and 5 missing.
U.S. Air Force losses by aircraft and flak included: 4 B-17G bombers lost (2 in the vicinity of Jena), 4 were damaged beyond repair, and 121 damaged (46 in the vicinity of Jena); 9 airmen were Killed In Action (KIA), 5 Wounded In Action (WIA), and 49 Missing In Action (MIA).
Luftwaffe losses this day over Germany amounted to a total of 41 aircraft destroyed, 3 likely damaged beyond repair, and 19 missing; these losses included 3 Me 262 aircraft. The U.S.A.F. total losses amounted to 6 bombers and 10 fighters are lost.
Jena in March 1945 was a transit center with people coming in and out, and with fluctuating numbers of refugees and forced laborers too so it is likely the exact number of casualties on the ground during these air raids will ever be known.
A memorial was established at the Rathausgasse of Jena, and here every 19th of March the dead of that bombing raid are remembered with a wreath. To this day this is a difficult commemoration because many citizens see that event, and the postwar partition of Germany too, as part of what resulted from the actions of the Nazi party. In Jena too there had been Nazi era perpetrators, who as one publication explained “were guilty of the exclusion, persecution and murder of many people”. Another memorial the “Stele zur Judenverfolgung und KZ-Zwangsarbeit” in Jena was established at the Löbstedter Straße 56, this commemorates prewar Jewish residents who were interned at the behest of the Jena Mayor near the site, and this also marks the site of the satellite camp KZ Buchenwald eichsbahnausbesserungswerk (RAW) sub-camp in Jena.
On 9 April 1945 Jena was again attacked, this time it was the Primary Target for 86 B-26 “Marauder”, medium-range bombers of the 9th Bomber Division of the Ninth US Air Force. Between 16:14 to 16:53 they dropped 151 tons of bombs on Jena. The train station, the existing rolling stock, and approximately 105 surrounding buildings were largely destroyed. There were 108 deaths. In addition, another 6 aircraft loaded with 11 tons of cluster bombs attacked the city antiaircraft positions.

Zeiss Ikon AG.的所在地：德累斯顿

德累斯顿被炸的原因，英美的报告罗列了诸多原因，这里是重要的军工生产基地，其中专门提到了上面Zeiss Ikon AG.蔡斯伊康

ESK 2000 照相枪的生产商：Zeiss Ikon AG.

至于楼主说的蔡司在德累斯顿轰炸后的损失。。
On February 13 & 14, the Allied air forces relentlessly bombed the city. In the Striesen section of the city, the Ica works of Zeiss Ikon was utterly devastated by this bombing with all of the upper floors of the mail building collapsed into the basement level where the technical drawings, prototypes and models had been stored. Zeiss Ikon had lost all of its capacity to manufacture 35-millimeter cameras with the loss of this factory complex. The loss of the plant was estimated at 80%. The nearby Ernemann facility, which had concentrated on darkroom and cinematic equipment, was struck as well but the damage was minor and estimated at 10%.
It became clear to Hubert that there was not longer a reason for him to remain in Dresden. He successfully retraced his steps back to his family in Austria where it was relatively safe. When the war became clearly lost, many of the German people started moving by foot toward what would become the Western zones since there was great fear of the Russian army. So again, Hubert took his family to the night trains with the goal of getting as close to the Stuttgart location of his employer. This was accomplished amid many harrowing situations and the commodities of sugar and cameras kept the family sheltered and fed.
2月13/14日，盟军火攻德累斯顿，玉石俱焚，位于Striesen区的蔡司伊康工厂80%的建筑被完全炸毁，地板砸进了地下掩体，所有技术图纸、相机原型模型都毁于一旦，蔡司伊康的35mm相机生产线已不复存在，附近的Ernemann工厂只有10%建筑受损，因此公暗房和电影器材基本保住了.对Nerwin来说留在德累斯顿已经没有任何意义，于是全家赶紧离开这里返回奥地利的老家，出于对俄国人的恐惧，德佬居民开始大批徒步逃往西部，Nerwin也再次带着全家乘坐夜行列车抵达斯图加特，一路上混乱不堪险象环生，不过靠着携带的砂糖和相机保证了全家没有挨饿.

以上来自时任蔡司伊康的相机设计主管Hubert Nerwin在战后的回忆，他在斯图加特参与了Contessa工厂的复产，生产出来的小型蔡司相机成为驻德米军小卖部的抢手货，后来，Nerwin作为回形针计划的一部分（米佬抢夺德佬优秀人才计划）先是加入了格拉菲后来跳槽去了柯达，1983年在纽约去世.
以上都来自谷歌。。